Boxcab Build, GRS Kit

[Doug]

I always fancied an old fashioned looking diesel or tram style locomotive. One of the GRS Boxcab diesel kits looked good. The small 0-4-0, or the Bo-Bo were the ones i liked the best. The Bo-Bo one is based on the prototype american BoxCab.

Here is a site with details of lots of prototypes:

http://sbiii.com/jfcageir/ageir.html

The Bo-Bo is similar to the AGEIR/GE Class B-B-120 loco

http://sbiii.com/jfcageir/ageir5.html


Here is the range of kits that GRS ( http://www.grsuk.com/ ) do:

 

[Doug]

In the end i went for the 0-4-0 version, however i decided to use a longer wheelbase USA Trains motor block as i felt the one recommended was too short.

I took a couple of shots of the example in the shop:

 

[Doug]

I felt a few more details needed to be added, to add more interest to the chassis and body, I also felt that the headlight looked better in the position it is on the prototype.

 

[Doug]

The kit comes as a set of parts cut from styrene sheet - quite acceptable as the prototype is a box!

 

[Doug]

It also comes with a large collection of white metal detailing parts. Nicely molded, although with a bit of flash on them.

 

[Doug]

I decided to change the buffer beams to look more like a tram loco, as i wanted it to look like it had been imported from a commonwealth country rather than direct from the USA:

 

[Doug]

The model is going to use the USA Trains 95mm wheelbase motor block. Powered by batteries, although it can be switched to track pick-up.

 

[Doug]

I'll first detail the chassis construction, then the power/control system, then the body and detailing.

The chassis frames had to be replaced as the motor block is slightly higher than the recommended one. I cut them from some thick styrene sheet from Eileen's Emporium. Some of the holes in the original ones had been drilled in the wrong place. The change in the wheelbase also meant some of the holes would have been in the wrong place for the different motor block anyway.

The metal detailing parts were glued in place with Devcon epoxy or Superglue. I added an access plate to one end of the frames and some extra rivets to suggest the interior construction of the chassis.

 

[Doug]

The beam that runs between the two axlebox springs had to be re-made due to the change to the wheelbase.

 

[Doug]

The chassis was assembled with replacement tram style buffer beams. Additional styrene strips were used to re-inforce the joins and to create location blocks to keep the motor block in place. View from underneath:

 

[Doug]

View from the side:

 

[Doug]

Primer sprayed on. The funny lump at one end is a DPDT switch covered in masking tape. I have subsequently added a second switch to the other side.

The strips on top of the chassis is to locate the body. The cut-out at the left hand end is to allow the sound from the speaker to get out!

 

[Doug]

Upside-down view with motor block in place:

 

[Doug]

The loco is to be powered by batteries. ModelPower ( http://store.modelpower.co.uk/ ) made up a custom battery pack for me: 9 sub-C, 4300 mAh cells. Arranged in a 3x3 configuration. This just fitted inside the body of the loco.

Modelpower also supplied the cable for connecting everything up and numerous Tamiya connectors to make up the charging wiring.

I made up a cradle to hold the battery pack inside it, with the electronics sitting on top:

 

[Doug]

The electronics consist of: Brian Jones MacFive Electronic speed controller, FX-4U soundcard (with Class 37 sound), LAMP-1 lighting control board, Futaba 2.4GHz reciever.

 

[Doug]

Here it is all in place:

 

[Doug]

Onto the body work!

First job is to clean up the window holes and sand down the sides and ends. The doors are made up of two layers, so they are glued together.

 

[Doug]

The roof comes as two pieces that need to be blued together. GRS do a similar roof section in 2 foot long mouldings and would probably have been easier to use than all the filling i had to do to get a good finish.

 

[Doug]

Then comes the fun bit! I wanted a rivetted body rather than a welded one. Just like the prototype. This meant lots of rivets, about 600 in all, i think!

First drill lots of holes, using a piece of veroboard as a jig for all the holes. This works quite well. As i was using a drill about half the diameter of the holes in the vero board it was difficult to get them all lined up. A bigger drill would be much easier as it can't wonder in the hole in the veroboard. As i used a small bit of veroboard i had to drill some holes, then move the veroboard along a bit, drill more holes etc etc. I found that it was difficult to get a straight line. In future use a longer bit of veroboard!

 

[Doug]

Then i added the strapping, and re-drilled all the holes from the inside